Advertising pays a large portion of the costs associated with the Internet. Typically, a content publisher receives revenue from an advertiser by including advertisements along with content provided to the browser-user when the browser-user requests a web page. Some publishers serve the advertisements from their own servers along with the content the browser-user requested. Other publishers rely on third-party ad servers by placing particular tags or scripts into the content sent to the browser-user. The browser-user interprets those tags or scripts as instructions to retrieve advertising information from the third-party ad server. The advertising information is presented to the browser-user along with the publisher's content. Though various methods are employed, the base model is that advertisers pay publishers for each ad that is requested by a browser-user on the basis of the tags or scripts within that publisher's content page.
An AD BLOCKER commonly inspects the material coming from a publisher, identifies tags or scripts that would cause advertising to appear along with the content, and instructs the browser to ignore or suppress those tags or scripts. Use of an Ad Blocker disrupts the advertising-pays funding model for the Internet. When only a few browser-users were blocking ads, the effect was minimal. But when large numbers of browser-users began to block ads, the publishers' revenue was threatened. Some publishers responded to Ad Blockers by changing their published documents to inspect the browser-user for evidence of ad blocking capability. Thus began a cat-and-mouse game of detection and counter-detection. By inserting their own scripts as part of the content of a page served to the browser-user, the publisher conditioned delivery of content on “well-behaved” browser-user configurations. When the publisher script detected the presence of ad-blocking capability, it refused to serve the content requested by the browser-user. The Ad Blockers responded by altering their methods to avoid detection by the publisher-advertiser scripts. The publishers responded by adapting to the new methods employed by the Ad Blockers. This cycle has repeated multiple times in the last few years. In one famous (or notorious) episode, the Springer publishing house in Germany announced triumphantly that it had circumvented existing ad blocking technology, only to have some Ad Blockers trump the Springer methods within a few hours.